A [3+3+3]-fragment coupling strategy was successfully applied in the synthesis of the nonacyclopeptide of chlorofusin, a potent natural antagonist against p53-MDM2 interactions. The accomplished convergent synthesis includes parallel syntheses of three tripeptides and their sequential assembly, and macrocyclization of the linear precursor to the required 27-membered nonacyclopeptide. (C) 2010 Elsevier Ltd. All rights reserved.